Cognitive complaint in mild cognitive impairment and Alzheimer's disease

Whereas the presence of a subjective memory complaint is a central criteria for mild cognitive impairment (MCI), little work has been done to empirically measure its nature and severity. The Self-Evaluation Questionnaire (QAM) assessed memory complaints relative to 10 domains of concrete activities of daily life in 68 persons with MCI, 26 persons with Alzheimer's disease (AD), and 81 healthy older adults. In addition, a neuropsychological battery was administered to assess whether subjective complaints were linked to actual cognitive performance. The findings indicate that individuals with MCI report more memory complaints than controls for a range of specific materials/circumstances. MCI and AD individuals did not differ in their level of memory complaints. Correlational analyses indicated that a higher level of memory complaints relative to conversations and to movies and books were associated with a higher level of objective cognitive deficits in persons with MCI but not in AD. Furthermore, complaints increased in parallel with global cognitive deficits in MCI. These results suggest that persons with MCI report more memory complaints than healthy older controls, but only in specific domains and circumstances, and that anosognosia is more characteristic of the demented than of the MCI phase of Alzheimer's disease.